A variable valve-operating device for an internal combustion engine is known in which a cam carrier is fitted around a cam shaft of an engine valve train in a manner to be prevented from relative rotation relative to the cam shaft and to be slidable in an axial direction. The cam carrier has a plurality of cam lobes formed on the outer circumferential surface of the cam carrier. The cam lobes have different cam profiles determining valve actuation characteristics. The cam carrier is moved in the axial direction so that the different cam lobes can act on the engine valve to change valve actuation characteristics (see Patent Document 1, for example).